Electric test-meter.



49 6 G45 53AM G. A. SOHEEPFER.

ELECTRIC TEST METER.

APPLIOATION FILED OUT. 21, 1910.

Patented Aug. 25, 1914.

2 8HEETS-SHBET 1.

THE NORRIS PETERS C0, PHOTO-LITHO \VASH!NOTON, D. C

G. A. SGHEBFFER.

ELECTRIC TEST METER.

APPLICATION TILED 0011.21, 1910.

1 1 08,40 1 Patented Aug. 25, 1914.

2 SHEETS-SHEET 2.

Witnesses: [nvezuar G 22006 AMSGhBf/i" Atdvrneys THE .IuRRls PETERS CO. r noTaL/rna. WASMINGTUN. D. II.

UNITED STATES PATENT onnron.

GUSTAVE A. sonnnrrnn, or InnIANArotIs, INDIANA, Assrdnon, BY MESNE AssIeN MENTS, T0 ROLLER SMITH 00., NEW YORK, N. Y., A CORPORATION OF NEW YORK.

nnnornrc TEST-METER.

To all whom it may concern Be it known that I, Gns'mvn A. SCI-IEEF- ran, a citizen of: the United States, residing at Indianapolis, in the county of Marion and State of Indiana, have invented a cer' tain new and Improved Electric Test-Meter,

of which. the following is a full, clear, con

else, and exact description, reference being had to the accompanying drawings, forming a part oi thisspecitication.

invention relates to an improved form oi electric test meter adapted to be used without auxiliary apparatustor testing elec trio meters of different standard makes.

By my invention I provide a plurality of meter terminals which may be provided with proper designations to indicate the j make of meter to be connected with each terminal to properly test such meter. The

terminals are so connected to the windings of the test meter either by means of proper resistances or by direct connection with the diliercnt portions of the meter windings that thc rate of operation oi the test meter is different for connections efiected with the l different terminals such rates of operation being proportional or corresponding to the indicated makes of meters to he tested.

As is well known in the art each standard make of electric meters is constructed. with certain definite proportions and resistances of windings as a result of which it has a definite rate of rotation for any given voltage and load current, which rate, however, is different from the rates of rotation of other makes for the same values or voltage and load current. As a result by providing the resistances between the terminals ofmy test meter so that they will produce rates ofrotation of the test meter. corresponding with the rates of rotation of the meters to be tested,all that is necessary is to properly connect the series winding of the test meter in circuit with the series winding of the meter to be tested and also with the load to be employed and also to connectwpressure circuits of the test me ter. and the meter to be tested to the line extending to the source of current.

Care must be taken to properly connect the terminals of the test meter according to the a make otmeter to be tested and no external Specification of Letters Patent.

shunts or resistances are required. The terminals provided on the testmeter for different makes of meters to be tested may be replaced if desired by a single terminal connccted with regulating or switch mechanism for establishing conditions of operation of the test meter similar to those above de-y the pressure circuit of the meter and entending to a corresponding number oii difterent terminals. Fig. 2 is a diagrammatic view of the terminals of one end of the pressure circuit indicated in Fig. 1, showing a diflierent disposition of the resistance connected with such terminals. Fig. 3 shows in amodified diagrammatic view switching mechanism that may be employed to establish different operative conditions by means of a single terminal for the end of the pres sure circuit indicated. Fig. 4 shows in a diagrammatic View similar to Fig. 1. connections of the meter terminals to different points of the series circuit of the meterby Patented Aug. 25, 1914. Application filed October 21, 1910. Serial No. 588,265.

mg conditions upon any voltage between the which the diiterent operating conditions required may be secured by including more or less of the series field. coil in circuit with the load. Fig. 5 shows in a diagrammatic view switching mechanism adapted to secure the results indicated in Fig. 4 with the use of but one terminal at each end of the series circuit of the test meter. Fig. 6 shows, in adiagrammatic viewyan arrangement of circuits by which the series field coil of the meter is adapted. to he shunted to a greater or lessydegree by means of a contact plug and cooperating contacts to secure different rates of operation of the meter mechanism. Fig. 7 shows ina view similar to Fig. 1 an arrangement of resistances adapted to shunt the armature circuit as desired to produce rates of operation corresponding to different meters to be tested.

Similar numerals refer to similar parts throughout the several views.

As shown in Figs. 1 and 2, the meter consists essentially of a rotatable armature 1 mounted upon a shaft 2 to which is secured a commutator 3 connected with the windings of-the armature. The commutator 3 has bearing thereon brushes 4 and The brush 4 is directly connected with the binding post 6 by wire 7 and is also connected with the series coil 8, the other terminal of which is connected by wire 9 with the binding post 10. The brush 5 is connected by wire 11 with the starting or compensating field coil 12, the other terminal of which is connected by wire 13 with a main resistance 14', the other terminal of which is connected by wire15 with the binding post 16. Additional binding posts 17, 18 and 19 are associated with the binding post 16 in such a manner that the resistance 20 is included between the binding posts '16 and 17; the resistances 21 between the binding posts 17 and 18, and the resistance 22 between the binding posts 18 and 19. A base 23 is indicated to support the various parts of the meter structure.

The resistances 20, 21 and 22 are so proportioned that when they are included in circuit with the starting coil 12 by connecting to the binding posts 17, 18 and 19 different rates of operation of the meter armature 1 are secured correspondingto the rates of" rotation of different standard makes of meters to be tested which may be designated by proper indications "in any suitable manner, such indications being made inthe constructionshown in Figs. 1 and 2 by the letters A, B, G and D, the meaning of these designations being that when testing a commercial meter of make D connection is made acrossjthe line extending to the source of current by -bmding posts 6 and 16; when EVCOHIIIIBI'ClEtl meter of make C is to be tested, connection is made across the line extending to the source of currentby bindingposts 6 and 17 when a commercial meter of'make B is to "be tested connection is made across*the line extending to the source of current by'means of binding posts 6 and 18;--and when a 'commercial* meter=of make" A is to be tested connection 1s made across'the llnewire, the load "and the' serieswindingor i windings'of the meter being tested.

' In the modified arrangement-*shownv in Fig. 2ithe resistances 24-, '25. and'26 'corre sponding to the -sresistances 20, 21 a; and? 22 shown in Fig. 1, are connected directly from the posts 17, 18 and 19 respectively to the wire 15. This arrangement provides that any of the resistances 24, 25 and 26 may be changed if necessary to accommodate other makes of meters to be tested without interfering with the remaining resistances.

In the modification shown in Fig. 3 the wire 15 is connected with the pivotal point of a switch arm 27 adapted to engage different contact buttons 28, 29, 30 and 31 between which the resistances 20, 21 and 22 are connected. The button 31 is connected by wire 32 with a binding post 33 which constitutes one terminal of the pressure circuit of the meter, the other terminal of which is the binding post 6 shown in Fig.

'1. The switch arm 27 and contact buttons engaged thereby may be located preferably outside of the meter casing indicated by the dotted line 40 and supported by the base of the test meter so as to be convenient of access tothe operator.

In the modified construction shown in Fig. 4 wire 15 is connected directly to the binding post 33 and the series field coil Sis provided with a plurality of taps 34, 35 and 36 extending to the binding posts 37,38 and 39 respectively. The portions of the field coil 8 included between the taps 34, 35 and 36 and the wire 9 are so proportioned that by connecting the load circuit of the meter to the post 6 and one of the posts 37, 38, 39 and 10 .various operating conditions of the meter are secured corresponding to commercial makes of meters to be tested, as described above. The several makesbf meters to be tested areindicated by the letters A, B, C, D associated with the binding posts 37, 38, 39 and 10. For this-arrangement" of'the meter windings the pressure circuit of the test meter terminating in the binding posts 6 and'33 is connected across the line extending to the source of current, and the series circuit including the series winding iofthe meter to be tested and the load employed is connected withthe post 6 and the one of the posts'37, 38, 39 and 10 indicated by'one'of'the designations associatedwith the posts which corresponds 'with the make of meter to be tested.

In the 'modified. arrangement shownin Fig 5, the connections are: similar to those shownin Fig; 4 with? the exception that the leads 34, 35 and 36 extendto contact but- An additional contact switch arm 44 when itis desired to include in the series circuit all :of the field *coil 8. As a result of the arrangementshown in Fig.1 5, the 'switch arm 44=serves to short circuit moreor less o'fthe fieldcoil8 as desired thus serving to establish operating conditions of the meter mechanism corresponding to different makes "of meters to be tested indicated by the designations A, B, O and D associated with the buttons 41, 12, 43 and 46 respectively. The switch arm 4L4 and the contactsengaged thereby may, if desired, be located outside of the meter casing indicated by the dotted line so as to be readily accessibleto the operator.

As shown in l ig. 6, the series coil 8 is connected by the wire 9 directly to the binding post 10. The wire 9 has connected to it one terminal. of a resistance 47, the other terminal of which is connected to one of a pair of contacts 4-8, the other contact 49 of which is connected by wire 50 with wire 7. Tape 51 and 52 are taken oil from the re sistance 1-7 and connected. to contacts 53 and 54, arranged to cooperate respectively with contacts 55 and 56, which are connected to wire 50. Contacts l8 and 49 are so conformed and related to each other as to be engaged by a taper plug 57 of conducting material when such plug is inserted between the contac The contacts 53 and 55 are similarly conformed and disposed, as are also the contacts 5% and 56. The series connection oi the test meter is made to binding posts 6 and 10, regardless of the operating condition of the meter to be established, and then by inserting the plug 57 between the proper pair-of contacts an operating condition corresponding to the meter of manufacture A, B or C may be secured, since by so insertingthe plug 57 diii'erent amounts oi the resistance 47 are included in shunt of the series field coil 8, and thus difierent opcrating conditions oi the meter are produced, which gives a rate oi. operation of the testmeter corresponding to the rate of operation oi the meter being tested for the same amount of current flowing through the series circuits of the two meters. It is to be understood that when a meter of make D is to be tested, the plug 57 is not used, and that no shunt is closed around the series field coil 8.

p In the modified arrangement shown in Fig. 7 a wire 87 is connected with the wire 7 and extends to the contacts 58, 59 and 60, which coiiperate with contacts 61, G9 and 63, respectively, and are adapted to be engaged by a taper conducting plug 57 in a manner similar to that shown and described in connection with Fig. 6, as a result of which the contacts between which the plug is inserted are electrically connected together. A wire 67 serves to connect the wire 11 with one terminal of the resistance 64:, the other terminal. of which is connected to one terminal of the resistance 65 and also to the contact 63. lhe other terminal oi the resistance 65 is connected to one terminal of the resistance 66 and also to the contact 62.

The 'other terminalofthe resistance 66 is connected to contact 61. As aresult of the arrangement of the resistances described when the taper plug 57 inserted between any pair of contacts a corresponding amount of resistance is included in shunt of the armature brushes ll andb, and use result, the speed oi." rotation of the armature is changedrto correspond with the resistaime thus included in circuit. Theresistances 64K, 65 and 66 are so proportioned that the re suiting speed otoperation of the meter corresponds with the speed 01. operation for. similar conditionsoii meters of make A, .B and (I, respecistively, it being assumed in the present illustration that. meters of make A operate slower than do meters of make 13,.

while both operateslower than do meters of makeCf a a i hile I have shown my invention in the embodiments herein described, I do not, howeverplimitmyself to these exact con-j structionabut desire to claim any equiva-t lents that may suggest tlicinselves to those skilled in theart. a

l/Vhat I claim is:- a a 1. In an electric test meter, the combine;

tion of a rotatable armature, a main series field coil, an auxiliary pressure field coil, a controlling resistance in circuit 'with the auxiliary field coil, a phu'ality ot binding posts for terminating the pressure circuit of the meter, and fixed resistances betweenthe binding posts to produce rates of rotation of the armature corresponding to different meters to be tested.

2. In an electric test meter, the combination oi? a rotatable armature, a field coil, a plurality of binding posts for terminating the pressure circuit of the meter, and fixed resistances between the binding posts to produce operating conditions of the armature corresponding to different meters to be tested.

3. In an electric test meter, the combination of a rotatable armature, a field coil, resistances connected with the pressure c1rcuit of the meter for producing operating conditions of the armature corresponding to dinerent meters to be tested, and terminals for such resistances.

4. In an electric test meter, the combination of a rotatable armature, a field coil, a

plurality of binding posts for terminating the pressure circuit of the meter, fixed resistances between the binding posts to produce operating conditions of the armature corresponding to diiierent meters to be tested, and devices associated with the hind ing posts for indicating the corresponding meters to be tested. 1 r

5. In an electric test meter, the combination of a rotatable armature, a field coil, resistances connected with the pressure circuit of the meter for producing operating conditions of the armature corresponding to different meters to be tested, terminals for such resistances, and devices associated with the terminals for indicating the meters to be tested corresponding to the different steps.

6. In an electric test meter, the combina tion of a rotatable armature, a main series field coil, a compensating coil, acontrolling resistance in circuit with the compensating coil, and terminals connected with the resistance at points to produce different predetermined testing rates of rotation of the armature.

7. In an electric testmeter, the combination of a rotatable armature, a field coil, a controlling resistance, and terminals con- .nected with the resistance at points to produce different predetermined testing rates of rotation of the armature.

8. In an electric test meter, the combination of a rotatable armature, a main series field coil, a compensating coil, a controlling resistance in circuit with the compensating coil, terminals connected with the resistance at points to produce different predetermined testing rates of rotation of the armature, and means associated with the terminals for indicating the corresponding testing rates of rotation.

9. In anelectric test meter, the combination of a rotatable armature, a field coil, a

Copies of this patent may be 11. In an electric test meter, the combination of a rotatable armature, a main series field coil, an auxiliary pressure field coil, a controlling resistance in circuit with i the auxiliary field coil, a plurality of binding posts for terminating the pressure circuit of the meter, and fixed resistances between the binding posts'to produce difierent full load speeds of the armature corresponding to those of difierent meters to be tested.

In witness whereof, I hereunto subscribe my name this 18th day of October, A. D.,

GUSTAVE A. SCHEEFFER. WVitnesses:

PI-IoEBE HILL, J orm E. Soo'rT.

Washington. D. 0. 

